The present invention relates to a sheet ceramic package that comprises a plurality of product units such as ceramic substrates and circuit substrates for semiconductors. More particularly, the present invention relates to a sheet ceramic package that comprises a plurality of product units whose electrical characteristics can be inspected and evaluated--to determine, for example, whether they are electrically conductive or not--before breaking them up into separate, individual units.
Conventional sheet ceramic packages comprise a plurality of product units that can be separated into individual units by breaking them apart along break grooves, score lines, or other snap lines. Such conventional ceramic packages are constructed as follows. Dummy parts surround each individual product unit, separating the product units one from another along the snap lines. Each product unit has conductive lines which serve to provide external electrical connection points to a semiconductor therein. Interconnecting conductor patterns are set on the dummy parts and serve to interconnect all the conductive lines of all the product units for the purpose of electroplating. The electroplating provides a plating of high conductivity and corrosion resistant materials.
In such sheet ceramic packages, the semiconductor is packaged into each product unit, which is then hermetically sealed. The individual units are then broken apart along the snap lines. Each unit thus broken up is then placed on an inspection jig where its electrical characteristics are determined using each solder pad pattern.
These conventional packages present disadvantages however. First, since the sheet is electroplated as a whole, all the inner layer conductors of the product units must be electrically connected. This is required by the electroplating process since all material to be plated must be charged with respect to a plating solution. Therefore, complete electrical interconnection is used to apply the correct potential. Accordingly, the electrical characteristics of the individual product units can be evaluated only when they are broken up into separate units. It is impossible to inspect the entire sheet at once. Second, to inspect product units, each must be placed on a jig. When its electrical characteristics are evaluated, each product unit must have the same surface, either its front or its back, facing in the same direction. This requirement makes the inspection quite troublesome.